Display apparatus

ABSTRACT

According to an aspect, a display apparatus includes: a first light-transmissive substrate; a second light-transmissive substrate arranged to face the first light-transmissive substrate; a liquid crystal layer including polymer dispersed liquid crystals sealed between the first light-transmissive substrate and the second light-transmissive substrate; at least one light-emitting device arranged to face at least one of a side surface of the first light-transmissive substrate or a side surface of the second light-transmissive substrate; and at least one reflector arranged on at least one of a side surface of the first light-transmissive substrate or a side surface of the second light-transmissive substrate, the side surface of the first or second light-transmissive substrate being on an opposite side of the side surface of the first or second light-transmissive substrate to which the at least one light-emitting device faces, and configured to reflect light at the side surface on the opposite side.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from Japanese Application No.2016-151455, filed on Aug. 1, 2016, the contents of which areincorporated by reference herein in its entirety.

BACKGROUND 1. Technical Field

The present disclosure relates to a display apparatus.

2. Description of the Related Art

Japanese Patent Application Laid-open Publication No. 2013-114947(JP-A-2013-114947) and Japanese Patent Application Laid-open PublicationNo. 2007-200741 (JP-A-2007-200741) describe a surface light sourcedevice or a so-called backlight device arranged on the back of a displaypanel. Japanese Patent Application Laid-open Publication No. 2010-230835(JP-A-2010-230835) describes a reflective liquid crystal displayapparatus including a sidelight, a side reflection plate, and areflection plate arranged on the back of a display panel.

In the display apparatuses of JP-A-2013-114947, JP-A-2010-230835, andJP-A-2007-200741, the backlight device arranged on the back of thedisplay panel or the reflection plate blocks background light on asecond surface side on the opposite side of a first surface of thedisplay panel, which makes it hard for a background on the secondsurface side to be visually recognized from the first surface of thedisplay panel.

For the foregoing reasons, there is a need for a display apparatus thatallows visual recognition, from one surface of a display panel, of abackground on the other surface side opposite to the one surface side,and suppresses an amount of light leaking from a second side surface ofthe display panel, the light having entered a first side surface of thedisplay panel.

SUMMARY

According to an aspect, a display apparatus includes: a firstlight-transmissive substrate; a second light-transmissive substratearranged to face the first light-transmissive substrate; a liquidcrystal layer including polymer dispersed liquid crystals sealed betweenthe first light-transmissive substrate and the second light-transmissivesubstrate; at least one light-emitting device arranged to face at leastone of a side surface of the first light-transmissive substrate or aside surface of the second light-transmissive substrate; and at leastone reflector arranged on at least one of a side surface of the firstlight-transmissive substrate or a side surface of the secondlight-transmissive substrate, the side surface of the first or secondlight-transmissive substrate being on an opposite side of the sidesurface of the first or second light-transmissive substrate to which theat least one light-emitting device faces, and configured to reflectlight at the side surface on the opposite side.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating an example of a displayapparatus according to a first embodiment;

FIG. 2 is a block diagram illustrating the display apparatus of FIG. 1;

FIG. 3 is a timing chart for describing timing to emit light by a lightsource in a field sequential method;

FIG. 4 is an explanatory diagram illustrating a relationship between avoltage applied to a pixel electrode and intensity of scattered light;

FIG. 5 is a cross-sectional view illustrating an example of across-section of the display apparatus of FIG. 1;

FIG. 6 is a plan view illustrating a plane of the display apparatus ofFIG. 1;

FIG. 7 is an enlarged cross-sectional view of a liquid crystal layersection of FIG. 5;

FIG. 8 is a cross-sectional view for describing a non-scattering statein the liquid crystal layer;

FIG. 9 is a cross-sectional view for describing a scattering state inthe liquid crystal layer;

FIG. 10 is a plan view illustrating a pixel;

FIG. 11 is a cross-sectional view illustrating a cross-section takenalong line XI-XI′ in FIG. 10;

FIG. 12 is a diagram for describing incident light from a light-emittingdevice;

FIG. 13 is a cross-sectional view illustrating another example of across-section taken along line V-V′ in FIG. 6;

FIG. 14 is a cross-sectional view illustrating a comparative example ofFIG. 13;

FIG. 15 is a schematic cross-sectional view for describing a state oflight reflected at a side surface when principal surfaces and sidesurfaces of light-transmissive substrates are at right angles;

FIG. 16 is a schematic cross-sectional view for describing a state oflight reflected at a side surface when principal surfaces and sidesurfaces of light-transmissive substrates are at right angles;

FIG. 17 is a schematic cross-sectional view for describing a state oflight reflected at a side surface when principal surfaces and sidesurfaces of light-transmissive substrates are not at right angles;

FIG. 18 is a schematic cross-sectional view for describing a state oflight reflected at a side surface when principal surfaces and sidesurfaces of light-transmissive substrates are not at right angles;

FIG. 19 is a cross-sectional view illustrating an example of across-section of a display apparatus according to a first modificationof the first embodiment;

FIG. 20 is a cross-sectional view illustrating an example of across-section of a display apparatus according to a second modificationof the first embodiment;

FIG. 21 is a cross-sectional view illustrating an example of across-section of a display apparatus according to a third modificationof the first embodiment;

FIG. 22 is a plan view illustrating a plane of a display apparatusaccording to a fourth modification of the first embodiment;

FIG. 23 is a cross-sectional view illustrating a cross-section takenalong line XXIII-XXIII′ in FIG. 22;

FIG. 24 is a plan view illustrating a plane of a display apparatusaccording to a second embodiment;

FIG. 25 is a cross-sectional view illustrating a cross-section takenalong line XXV-XXV′ in FIG. 24;

FIG. 26 is a cross-sectional view illustrating a cross-section takenalong line XXVI-XXVI′ in FIG. 24; and

FIG. 27 is an explanatory view for describing a method of manufacturinga reflector of the display apparatus according to the second embodiment.

DETAILED DESCRIPTION

Modes (embodiments) for carrying out the present disclosure will bedescribed in detail with reference to the drawings. The presentdisclosure is not limited by the descriptions of the followingembodiments. The elements described hereunder include those that can beeasily thought of by those skilled in the art and substantially the sameelements. The elements described hereunder may also be combined asappropriate. The disclosure is merely an example, and the presentdisclosure naturally encompasses appropriate modifications maintainingthe gist of the disclosure that is easily conceivable by those skilledin the art. To further clarify the description, a width, a thickness, ashape, and the like of each component may be schematically illustratedin the drawings as compared with an actual aspect. However, this ismerely an example and interpretation of the disclosure is not limitedthereto. The same elements as those described in the drawings that havealready been discussed are denoted by the same reference numeralsthroughout the description and the drawings, and detailed descriptionthereof will not be repeated in some cases. In this disclosure, when anelement is described as being “on” another element, the element can bedirectly on the other element, or there can be one or more elementsbetween the element and the other element.

First Embodiment

FIG. 1 is a perspective view illustrating an example of a displayapparatus according to a first embodiment. FIG. 2 is a block diagramillustrating the display apparatus of FIG. 1. FIG. 3 is a timing chartfor describing timing to emit light by a light source in a fieldsequential method.

As illustrated in FIG. 1, a display apparatus 1 includes a display panel2, a sidelight source device 3, and a drive circuit 4. In thisdescription, a direction on a plane of the display panel 2 is referredto as an X direction, a direction perpendicular to the X direction isreferred to as a Y direction, and a direction perpendicular to an X-Yplane is referred to as a Z direction.

The display panel 2 includes a first light-transmissive substrate 10, asecond light-transmissive substrate 20, and a liquid crystal layer 50(see FIG. 5). The second light-transmissive substrate 20 is arranged toface the first light-transmissive substrate 10 in a directionperpendicular to a surface of the first light-transmissive substrate 10(in the Z direction illustrated in FIG. 1). Polymer dispersed liquidcrystals described below are sealed in the liquid crystal layer 50 (seeFIG. 5) with the first light-transmissive substrate 10, the secondlight-transmissive substrate 20, and a sealant 19.

As illustrated in FIG. 1, the inside of the sealant 19 serves as adisplay area in the display panel 2. A plurality of pixels Pix isarranged in the display area in a matrix manner to have a row-columnconfiguration. In the present disclosure, a row refers to a pixel rowhaving m pixels Pix arranged in a direction, and a column refers to apixel column having n pixels Pix arranged in a direction perpendicularto the direction in which the rows are arranged. The values of m and nare determined according to a display resolution in the verticaldirection and a display resolution in the horizontal direction. Aplurality of scanning lines 12 is routed in respective rows and aplurality of signal lines 13 is routed in respective columns.

The sidelight source device 3 includes a light-emitting device 31, alight source controller 32, and a light source substrate 33 on which thelight-emitting device 31 and the light source controller 32 arearranged. The light source controller 32 is electrically coupled withthe drive circuit 4 through wiring of a flexible substrate (notillustrated), for example. The light-emitting device 31 and the lightsource controller 32 are electrically coupled with each other throughwiring in the light source substrate 33.

As illustrated in FIG. 1, the drive circuit 4 is fixed to a surface ofthe first light-transmissive substrate 10. As illustrated in FIG. 2, thedrive circuit 4 includes an input signal analyzer 41, a pixel controller42, a gate driver 43, a source driver 44, and a common potential driver45. The first light-transmissive substrate 10 has a larger area on an XYplane than that of the second light-transmissive substrate 20, and thedrive circuit 4 is provided on a portion of the first light-transmissivesubstrate 10 which is exposed from the second light-transmissivesubstrate 20.

An image input signal (e.g., RGB data) VS is input to the input signalanalyzer 41 from an image output device 91 of an external hostcontroller 9 through a flexible substrate 92.

The input signal analyzer 41 generates an image control signal VCS and abacklight control signal LCS on the basis of the image input signal VSinput from the outside. The backlight control signal LCS is a signalincluding information on a light amount of the light-emitting device 31set according to an average input gradation value to all the pixels Pix,for example. When a dark image is displayed, for example, the lightamount of the light-emitting device 31 is set to be small. When a brightimage is displayed, the light amount of the light-emitting device 31 isset to be large.

The image control signal VCS is a signal that determines a gradationvalue provided to each of the pixels Pix of the display panel 2. Inother words, the image control signal VCS is a signal includinggradation information regarding the gradation value of each of thepixels Pix. The pixel controller 42 performs correction processing suchas gamma correction and extension processing on an input gradation valueof the image control signal VCS to set the output gradation value. Thepixel controller 42 then generates a horizontal drive signal HDS and avertical drive signal VDS on the basis of the image control signal VCS.In the present embodiment, the light-emitting device 31 is driven by afield sequential method, and thus the horizontal drive signal HDS andthe vertical drive signal VDS are generated for each color that can beemitted by the light-emitting device 31.

The gate driver 43 sequentially selects each scanning line 12 of thedisplay panel 2 within one vertical scanning period in accordance withthe horizontal drive signal HDS. The order of selecting each scanningline 12 is arbitrary.

The source driver 44 supplies a gradation signal according to an outputgradation value of each pixel Pix to each signal line 13 of the displaypanel 2 within one horizontal scanning period in accordance with thevertical drive signal VDS.

In the first embodiment, the display panel 2 is an active matrix panel.Thus, the display panel 2 includes the signal (source) lines 13extending in the X direction and the scanning (gate) lines 12 extendingin the Y direction in plan view, and includes switching elements Tr atintersection portions of the respective signal lines 13 and therespective scanning lines 12.

A thin film transistor is used as the switching element Tr. Examples ofthe thin film transistor include, but are not limited to, a bottom gatetransistor and a top gate transistor. In the description, a single gatethin film transistor is exemplified as the switching element Tr, but adouble gate transistor may be used. One of a source electrode and adrain electrode of the switching element Tr is coupled with the signalline 13, a gate electrode is coupled with the scanning line 12, and theother of the source electrode and the drain electrode is coupled withone end of capacitance LC of liquid crystal. The capacitance LC of aliquid crystal has one end coupled with the switching element Tr througha pixel electrode 16, and the other end coupled with a common potentialCOM through a common electrode 22. The common potential COM is suppliedfrom a common potential driver 45.

The light-emitting device 31 includes a luminous body 34R of a firstcolor (e.g., red), a luminous body 34G of a second color (e.g., green),and a luminous body 34B of a third color (e.g., blue). The light sourcecontroller 32 controls the luminous body 34R of the first color, theluminous body 34G of the second color, and the luminous body 34B of thethird color to emit light in a time division manner. The luminous body34R of the first color, the luminous body 34G of the second color, andthe luminous body 34B of the third color are driven by the so-calledfield sequential method.

As illustrated in FIG. 3, in a first sub-frame (first predeterminedtime) RON, the luminous body 34R of the first color emits light, and thepixels Pix selected within one vertical scanning period GateScantransmit and display the light. At this time, in the entire displaypanel 2, if the gradation signal according to the output gradation valueof each of the pixels Pix selected within the one vertical scanningperiod GateScan is supplied to each of the above-described signal lines13, only the first color is lighted.

Next, in a second sub-frame (second predetermined time) GON, theluminous body 34G of the second color emits light, and the pixels Pixselected within the one vertical scanning period GateScan transmit anddisplay the light. At this time, in the entire display panel 2, if thegradation signal according to the output gradation value of each of thepixels Pix selected within the one vertical scanning period GateScan issupplied to each of the above-described signal lines 13, only the secondcolor is lighted.

Further, in a third sub-frame (third predetermined time) BON, theluminous body 34B of the third color emits light, and the pixels Pixselected within the one vertical scanning period GateScan transmit anddisplay the light. At this time, in the entire display panel 2, if thegradation signal according to the output gradation value of each of thepixels Pix selected within the one vertical scanning period GateScan issupplied to each of the above-described signal lines 13, only the thirdcolor is lighted.

The eyes of a human have a limited temporal resolution, and see anafterimage. Thus, the eyes of a human recognize a synthesized image ofthree colors in one-frame period. The field sequential method requiresno color filter, and suppresses an absorption loss in color filters,which can realize high transmittance. In a color filter method, onepixel is made of sub-pixels obtained by dividing the pixel into thefirst color, the second color, and the third color. On the other hand,the field sequential method does not require such division intosub-pixels, and thus can facilitate increase of the resolution.

FIG. 4 is an explanatory diagram illustrating a relationship between avoltage applied to a pixel electrode and intensity of scattered light.FIG. 5 is a cross-sectional view illustrating an example of across-section of the display apparatus of FIG. 1. FIG. 6 is a plan viewillustrating a plane of the display apparatus of FIG. 1. FIG. 7 is anenlarged cross-sectional view of a liquid crystal layer section of FIG.5. FIG. 8 is a cross-sectional view for describing a non-scatteringstate in the liquid crystal layer. FIG. 9 is a cross-sectional view fordescribing a scattering state in the liquid crystal layer.

If the gradation signal according to the output gradation value of eachof the pixels Pix selected within the one vertical scanning periodGateScan is supplied to each of the above-described signal lines 13, avoltage applied to the pixel electrode 16 is changed according to thegradation signal. If the voltage applied to the pixel electrode 16 ischanged, a voltage between the pixel electrode 16 and the commonelectrode 22 is changed. Then, as illustrated in FIG. 4, the scatteringstate of the liquid crystal layer 50 of each pixel Pix is controlled,and the intensity of scattered light of the pixel Pix is changed,according to the voltage applied to the pixel electrode 16.

As illustrated in FIGS. 5 and 6, the first light-transmissive substrate10 includes a first principal surface 10A, a second principal surface10B, a first side surface 10C, a second side surface 10D, a third sidesurface 10E, and a fourth side surface 10F. The first principal surface10A and the second principal surface 10B are planes parallel to eachother. The first side surface 10C and the second side surface 10D areplanes parallel to each other. The third side surface 10E and the fourthside surface 10F are planes parallel to each other.

As illustrated in FIGS. 5 and 6, the second light-transmissive substrate20 includes a first principal surface 20A, a second principal surface20B, a first side surface 20C, a second side surface 20D, a third sidesurface 20E, and a fourth side surface 20F. The first principal surface20A and the second principal surface 20B are planes parallel to eachother. The first side surface 20C and the second side surface 20D areplanes parallel to each other. The third side surface 20E and the fourthside surface 20F are planes parallel to each other.

As illustrated in FIGS. 5 and 6, the light-emitting device 31 isprovided to face the first side surface 20C of the secondlight-transmissive substrate 20. As illustrated in FIG. 5, thelight-emitting device 31 irradiates the first side surface 20C of thesecond light-transmissive substrate 20 with light L. The first sidesurface 20C, which faces the light-emitting device 31, of the secondlight-transmissive substrate 20 serves as a light incident surface. Agap G is provided between the light-emitting device 31 and the lightincident surface. The gap G serves as an air layer.

As illustrated in FIG. 5, the light L emitted from the light-emittingdevice 31 propagates in a direction away from the first side surface 20Cwhile being reflected at the first principal surface 10A of the firstlight-transmissive substrate 10 and the first principal surface 20A ofthe second light-transmissive substrate 20. When the light L proceedsfrom the first principal surface 10A of the first light-transmissivesubstrate 10 or the first principal surface 20A of the secondlight-transmissive substrate 20 toward the outside, the light L proceedsfrom a medium having a large refractive index to a medium having a smallrefractive index. Thus, if an incident angle of the light L entering thefirst principal surface 10A of the first light-transmissive substrate 10or the first principal surface 20A of the second light-transmissivesubstrate 20 is larger than a critical angle, the light L is totallyreflected at the first principal surface 10A of the firstlight-transmissive substrate 10 or the first principal surface 20A ofthe second light-transmissive substrate 20.

As illustrated in FIG. 5, the light L that has propagated through thefirst light-transmissive substrate 10 and the second light-transmissivesubstrate 20 is scattered in the pixel Pix having a liquid crystal inthe scattering state, and scattered light with the incident anglesmaller than the critical angle is radiated from the first principalsurface 10A of the first light-transmissive substrate 10 or the firstprincipal surface 20A of the second light-transmissive substrate 20 tothe outside. The light radiated from the first principal surface 10A ofthe first light-transmissive substrate 10 or the first principal surface20A of the second light-transmissive substrate 20 is observed by anobserver. The following describes the polymer dispersed liquid crystalsin a scattering state and the polymer dispersed liquid crystals in anon-scattering state with reference to FIGS. 7 to 9.

As illustrated in FIG. 7, the first light-transmissive substrate 10 isprovided with a first orientation film 55. The second light-transmissivesubstrate 20 is provided with a second orientation film 56. The firstorientation film 55 and the second orientation film 56 are, for example,vertical orientation films.

A solution in which liquid crystals are dispersed in monomers is sealedbetween the first light-transmissive substrate 10 and the secondlight-transmissive substrate 20. Next, the monomers are polymerized byultraviolet rays or heat in a state where the monomers and the liquidcrystals are oriented by the first orientation film 55 and the secondorientation film 56 to form a bulk 51. This process forms the liquidcrystal layer 50 including the polymer dispersed liquid crystals in areverse mode in which the liquid crystals are dispersed in gaps of apolymer network formed in a mesh manner.

In this way, the liquid crystal layer 50 includes the bulk 51 formed ofthe polymer, and a plurality of fine particles 52 dispersed in the bulk51. The fine particles 52 are formed of the liquid crystals. The bulk 51and the fine particles 52 each have optical anisotropy.

The orientation of the liquid crystals included in the fine particles 52is controlled by a voltage difference between the pixel electrode 16 andthe common electrode 22. The orientation of the liquid crystals ischanged by the voltage applied to the pixel electrode 16. The degree ofscattering of the light that passes through the pixel Pix is changed inaccordance with the change of the orientation of the liquid crystals.

For example, as illustrated in FIG. 8, in a state in which no voltage isapplied between the pixel electrode 16 and the common electrode 22, thedirection of an optical axis Ax1 of the bulk 51 and the direction of anoptical axis Ax2 of the fine particle 52 are the same. The optical axisAx2 of the fine particle 52 is parallel to the Z direction of the liquidcrystal layer 50. The optical axis Ax1 of the bulk 51 is parallel to theZ direction of the liquid crystal layer 50 regardless of whether or nota voltage is applied thereto.

An ordinary light refractive index of the bulk 51 and that of the fineparticles 52 are equal to each other. A light refractive index of thebulk 51 and that of the fine particles 52 are equal to each other. In astate in which no voltage is applied between the pixel electrode 16 andthe common electrode 22, a difference in the refractive indexes betweenthe bulk 51 and the fine particles 52 becomes zero in all directions.The liquid crystal layer 50 becomes the non-scattering state in whichthe liquid crystal layer 50 does not scatter the light L. The light Lpropagates in a direction away from the light-emitting device 31 whilebeing reflected at the first principal surface 10A of the firstlight-transmissive substrate 10 and the first principal surface 20A ofthe second light-transmissive substrate 20. When the liquid crystallayer 50 is in the non-scattering state in which the liquid crystallayer 50 does not scatter the light L, a background on the firstprincipal surface 20A side of the second light-transmissive substrate 20is visually recognized from the first principal surface 10A of the firstlight-transmissive substrate 10, and a background on the first principalsurface 10A side of the first light-transmissive substrate 10 isvisually recognized from the first principal surface 20A of the secondlight-transmissive substrate 20.

As illustrated in FIG. 9, the optical axis Ax2 of the fine particle 52is inclined by an electric field formed between the pixel electrode 16and the common electrode 22 to which a voltage is applied. Since theoptical axis Ax1 of the bulk 51 remains unchanged by the electric field,the direction of the optical axis Ax1 of the bulk 51 and the directionof the optical axis Ax2 of the fine particle 52 are different from eachother. The light L is scattered in the pixel Pix having the pixelelectrode 16 to which a voltage is applied. As described above, a partof the scattered light L radiated from the first principal surface 10Aof the first light-transmissive substrate 10 or the first principalsurface 20A of the second light-transmissive substrate 20 to the outsideis observed by an observer.

The display apparatus 1 of the first embodiment displays an image bycombining the pixel Pix having the pixel electrode 16 to which a voltageis applied and the pixel Pix having the pixel electrode 16 to which novoltage is applied. In the pixel Pix having the pixel electrode 16 towhich no voltage is applied, the background on the first principalsurface 20A side of the second light-transmissive substrate 20 isvisually recognized from the first principal surface 10A of the firstlight-transmissive substrate 10, and the background on the firstprincipal surface 10A side of the first light-transmissive substrate 10is visually recognized from the first principal surface 20A of thesecond light-transmissive substrate 20. The image displayed by the lightL scattered and radiated to the outside from the pixel Pix having thepixel electrode 16 to which a voltage is applied superimposes thebackground to be displayed.

FIG. 10 is a plan view illustrating a pixel. FIG. 11 is across-sectional view illustrating a cross-section taken along lineXI-XI′ in FIG. 10. As illustrated in FIGS. 1, 4, and 10, the firstlight-transmissive substrate 10 is provided with the signal lines 13 andthe scanning lines 12 in a grid manner in plan view. A region surroundedby adjacent scanning lines 12 and adjacent signal lines 13 is the pixelPix. The pixel Pix is provided with the pixel electrode 16 and theswitching element Tr. In the first embodiment, the switching element Tris a bottom gate thin film transistor. The switching element Tr includesa semiconductor layer 15 superimposed on a gate electrode 12Gelectrically coupled with the scanning line 12 in plan view.

The scanning line 12 is wiring made of a metal such as molybdenum (Mo)or aluminum (Al), a layered body of the aforementioned metal, or analloy of the aforementioned metal. The signal line 13 is wiring made ofa metal such as aluminum, or an alloy.

The semiconductor layer 15 is provided not to protrude from the gateelectrode 12G in plan view. This configuration causes the light Lproceeding from the gate electrode 12G side toward the semiconductorlayer 15 to be reflected, and is less likely to cause leakage of lightin the semiconductor layer 15.

As illustrated in FIG. 10, a source electrode 13S electrically coupledwith the signal line 13 is superimposed on one end portion of thesemiconductor layer 15 in plan view.

As illustrated in FIG. 10, a drain electrode 14D is provided in aposition adjacent to the source electrode 13S across a central portionof the semiconductor layer 15 in plan view. The drain electrode 14D issuperimposed on the other end portion of the semiconductor layer 15 inplan view. A portion of the semiconductor layer 15 not superimposed onthe source electrode 13S and the drain electrode 14D functions as achannel of the switching element Tr. As illustrated in FIG. 11,conductive wiring 14 coupled with the drain electrode 14D iselectrically coupled with the pixel electrode 16 through a through holeSH.

As illustrated in FIG. 11, the first light-transmissive substrate 10includes a first base material 11 formed of glass, for example. Thefirst base material 11 may be a formed of a resin such as polyethyleneterephthalate as long as the resin has light-transmissive properties. Afirst insulating layer 17 a is provided on the first base material 11,and the scanning line 12 and the gate electrode 12G are provided on thefirst insulating layer 17 a. A second insulating layer 17 b is providedto cover the scanning line 12. The first insulating layer 17 a and thesecond insulating layer 17 b are formed of a transparent inorganicinsulating member such as silicon nitride.

The semiconductor layer 15 is stacked on the second insulating layer 17b. The semiconductor layer 15 is formed of amorphous silicon. However,the semiconductor layer 15 may be formed of polysilicon or an oxidesemiconductor.

The source electrode 13 S that covers a part of the semiconductor layer15, the signal line 13, and the drain electrode 14D that covers a partof the semiconductor layer 15 are provided on the second insulatinglayer 17 b. The signal line 13 and the drain electrode 14D are formed ofthe same material. A third insulating layer 17 c is provided on thesemiconductor layer 15, the signal line 13, and the drain electrode 14D.The third insulating layer 17 c is formed of a transparent inorganicinsulating member such as silicon nitride.

The pixel electrode 16 is provided on the third insulating layer 17 c.The pixel electrode 16 is formed of a light-transmissive conductivemember such as indium tin oxide (ITO). The pixel electrode 16 iselectrically coupled with the conductive wiring 14 and the drainelectrode 14D through a contact hole provided in the third insulatinglayer 17 c. The first orientation film 55 is provided on the pixelelectrode 16.

The second light-transmissive substrate 20 includes a second basematerial 21 formed of glass, for example. The second base material 21may be a resin such as polyethylene terephthalate as long as the resinhas light-transmissive properties. The common electrode 22 is providedon the second base material 21. The common electrode 22 is formed of alight-transmissive conductive member such as ITO. The second orientationfilm 56 is provided on the common electrode 22.

FIG. 12 is a diagram for describing incident light from a light-emittingdevice. When the light from the light-emitting device 31 enters thefirst side surface 20C of the second light-transmissive substrate 20 atan angle θ0, the light enters the first principal surface 20A of thesecond light-transmissive substrate 20 at an angle i1. If the angle i1is larger than the critical angle, the light totally reflected at thefirst principal surface 20A of the second light-transmissive substrate20 at an angle i2 propagates through the second light-transmissivesubstrate 20. Since the gap G is provided between the light-emittingdevice 31 and the first side surface 20C (light incident surface)illustrated in FIG. 12, light LN with an angle θN by which the angle i1becomes smaller than the critical angle is not guided to the first sidesurface 20C of the second light-transmissive substrate 20.

FIG. 13 is a cross-sectional view illustrating another example of across-section taken along line V-V′ in FIG. 6. FIG. 14 is across-sectional view of a comparative example of FIG. 13. The displayapparatus of the first embodiment is provided with a reflector 60 thatreflects light, on the second side surface 20D of the secondlight-transmissive substrate 20, as illustrated in FIGS. 5, 6, and 13.The second side surface 20D is perpendicular to the first principalsurface 20A of the second light-transmissive substrate 20. Thus, even ifthe light L has been totally reflected at the first principal surface10A of the first light-transmissive substrate 10 or the first principalsurface 20A of the second light-transmissive substrate 20, an angle ofthe light L entering the second side surface 20D becomes smaller thanthe critical angle. In a display apparatus of a comparative exampleillustrated in FIG. 14, in which no reflector 60 is provided, lightleaks from the second side surface 20D, and the light amount in a regionA2 close to the second side surface 20D becomes smaller than that in aregion A1 close to the light-emitting device 31, as illustrated in FIG.6.

In contrast, the display apparatus of the first embodiment is providedwith the reflector 60 that reflects the light, on the second sidesurface 20D of the second light-transmissive substrate 20, asillustrated in FIGS. 5, 6, and 13. The reflector 60 includes areflection layer 61, and a light-transmissive adhesive layer 62 thataffixes the reflection layer 61 to the second side surface 20D. Thereflection layer 61 is formed of aluminum or silver, for example, in afilm manner, and can employ any material as long as the material hashigh reflectance. The adhesive layer 62 is an optical elastic resin thatfixes the reflection layer 61 to the second side surface 20D byultraviolet curing. The refractive index of the adhesive layer 62 ispreferably equal to or less than that of the first light-transmissivesubstrate 10 or the second light-transmissive substrate 20.

FIGS. 15 and 16 are schematic cross-sectional views each describing astate of light reflected at a side surface when principal surfaces andside surfaces of light-transmissive substrates are at right angles.FIGS. 17 and 18 are schematic cross-sectional views each describing astate of light reflected at a side surface when principal surfaces andside surfaces of a light-transmissive substrate are not at right angles.In FIGS. 15 and 16, an angle at which the light is totally reflected atthe first principal surface 10A of the first light-transmissivesubstrate 10 or the first principal surface 20A of the secondlight-transmissive substrate 20 is a critical angle i. As illustrated inFIGS. 15 and 16, in the first embodiment, the first principal surface20A and the second side surface 20D of the second light-transmissivesubstrate 20 are perpendicular to each other. This configuration allowsthe light that has been totally reflected at the first principal surface10A of the first light-transmissive substrate 10 or the first principalsurface 20A of the second light-transmissive substrate 20 to be totallyreflected at the first principal surface 10A of the firstlight-transmissive substrate 10 or the first principal surface 20A ofthe second light-transmissive substrate 20 even after having beenreflected at the second side surface 20D by the reflector 60.

In contrast, as illustrated in FIG. 17, when the first principal surface20A and the second side surface 20D of the second light-transmissivesubstrate 20 are inclined by an angle a, an inclination corresponding tothe angle α is added to the angle at which the light is reflected at thesecond side surface 20D, which increases the amount of light enteringthe first principal surface 20A of the second light-transmissivesubstrate 20 at an angle smaller than the critical angle i, and causeslight leakage from the first principal surface 20A of the secondlight-transmissive substrate 20.

Similarly, as illustrated in FIG. 18, when the first principal surface20A and the second side surface 20D of the second light-transmissivesubstrate 20 are inclined at an angle β, an inclination corresponding tothe angle β is added to the angle at which the light is reflected at thesecond side surface 20D, which increases the amount of light enteringthe first principal surface 10A of the first light-transmissivesubstrate 10 at an angle smaller than the critical angle i, and causeslight leakage from the first principal surface 10A of the firstlight-transmissive substrate 10.

As described above, in the first embodiment, the first principal surface20A and the second side surface 20D of the second light-transmissivesubstrate 20 being at right angles can cause the light reflected by thereflector 60 to be more easily reflected at the first principal surface20A of the second light-transmissive substrate 20.

The display apparatus 1 of the first embodiment includes the firstlight-transmissive substrate 10, the second light-transmissive substrate20, the liquid crystal layer 50, the light-emitting device 31, and thereflector 60. The second light-transmissive substrate 20 is arranged toface the first light-transmissive substrate 10. The liquid crystal layer50 includes the polymer dispersed liquid crystals sealed between thefirst light-transmissive substrate 10 and the second light-transmissivesubstrate 20. The light-emitting device 31 is arranged to face the firstside surface 20C of the second light-transmissive substrate 20. Thereflector 60 is arranged on the second side surface 20D on the oppositeside of the first side surface 20C on the light-emitting device 31 side,and the reflector 60 reflects the light at the second side surface 20D.According to this configuration, a backlight device or a reflectionplate is not provided on the first principal surface 10A side of thefirst light-transmissive substrate 10 or the first principal surface 20Aside of the second light-transmissive substrate 20. Therefore, thebackground on the first principal surface 20A side of the secondlight-transmissive substrate 20 is visually recognized from the firstprincipal surface 10A of the first light-transmissive substrate 10, orthe background on the first principal surface 10A side of the firstlight-transmissive substrate 10 is visually recognized from the firstprincipal surface 20A of the second light-transmissive substrate 20. Thelight is reflected at the second side surface 20D by the reflector 60,and thus a difference in the light amount between the region A2 close tothe second side surface 20D and the region A1 close to thelight-emitting device 31 becomes small, as illustrated in FIG. 6.

Further, the display apparatus 1 of the first embodiment does notinclude a polarizing plate on the first principal surface 10A side ofthe first light-transmissive substrate 10 or the first principal surface20A side of the second light-transmissive substrate 20. Therefore, whenthe background on the first principal surface 20A side of the secondlight-transmissive substrate 20 from the first principal surface 10A ofthe first light-transmissive substrate 10, or when the background on thefirst principal surface 10A side of the first light-transmissivesubstrate 10 from the first principal surface 20A of the secondlight-transmissive substrate 20 are observed, the background can bevisually recognized in a clear manner because of high transmittance.

First Modification of First Embodiment

FIG. 19 is a cross-sectional view illustrating an example of across-section of a display apparatus according to a first modificationof the first embodiment. The same configuration elements as thosedescribed in the above first embodiment are denoted with the samereference signs, and overlapping description is omitted.

A reflector 65 of the first modification of the first embodiment isobtained by solidifying metal particles of aluminum or silver to have apaste form. Any material can be used for the reflector 65 as long as thematerial has high reflectance. To apply the reflection portion 65 to theentire surface of a second side surface 20D of a secondlight-transmissive substrate 20, a part of the reflector 65 shouldprotrude to a first principal surface 20A of the secondlight-transmissive substrate 20. A paste edge portion 65 e that is anedge of the paste is preferably provided on the second side surface 20Dside without extending to an end portion 19 e on the second side surface20D side of a sealant 19. This configuration lowers a possibility of thepaste edge portion 65 e influencing a display region of a displayapparatus 1.

Second Modification of First Embodiment

FIG. 20 is a cross-sectional view illustrating an example of across-section of a display apparatus according to a second modificationof the first embodiment. The same configuration elements as thosedescribed in the above first embodiment are denoted with the samereference signs, and overlapping description is omitted.

A reflector 60 of the second modification of the first embodiment is aretroreflection structural body that enables retroreflection in whichlight having entered the retroreflection structural body at an incidentangle is reflected at an emission angle that is the same angle as theincident angle. The reflector 60 includes a reflection base material 63,a light-transmissive spherical body 64, and an adhesive layer 62. Thereflection base material 63 is a metal film made of aluminum or silver,and can employ any material as long as the material has highreflectance. The light-transmissive spherical body 64 is formed of glassor the like. For example, as illustrated in FIG. 20, light havingentered the reflector 60 at an angle i4 with respect to a second sidesurface 20D of a second light-transmissive substrate 20 is concentratedin one point by lens effect, is reflected at a bottom portion of thelight-transmissive spherical body 64, and is emitted from the reflector60 at the angle i4 with respect to the second side surface 20D of thesecond light-transmissive substrate 20. Similarly, light having enteredthe reflector 60 at an angle i5 with respect to the second side surface20D of the second light-transmissive substrate 20, which is differentfrom the angle i4, is concentrated in one point by lens effect, isreflected at the bottom portion of the light-transmissive spherical body64, and is emitted from the reflector 60 at the angle i5 with respect tothe second side surface 20D of the second light-transmissive substrate20.

When the reflector 60 is the retroreflection structural body, light canbe reflected in a direction parallel to a direction in which the lighthas entered. Thus, even if the second side surface 20D of the secondlight-transmissive substrate 20 is not at a right angle with a firstprincipal surface 20A of the second light-transmissive substrate 20, thelight reflected at the reflector 60 can be more easily reflected at thefirst principal surface 20A of the second light-transmissive substrate20.

According to another aspect, the reflector 60 may be a retroreflectionstructural body including a prism layer that enables retroreflection inwhich light having entered the retroreflection structural body at anincident angle is reflected at an emission angle that is the same angleas the incident angle.

Third Modification of First Embodiment

FIG. 21 is a cross-sectional view illustrating an example of across-section of a display apparatus according to a third modificationof the first embodiment. The same configuration elements as thosedescribed in the above first embodiment are denoted with the samereference signs, and overlapping description is omitted.

A display apparatus 1 according to the third modification of the firstembodiment includes a first light-transmissive substrate 10, a secondlight-transmissive substrate 20, a liquid crystal layer 50, alight-emitting device 31, and reflectors 60. The light-emitting device31 is arranged to face a first side surface 10C of the firstlight-transmissive substrate 10 and a first side surface 20C of thesecond light-transmissive substrate 20. One reflector 60 is arranged ona second side surface 20D on the opposite side of the first side surface20C on the light-emitting device 31 side, and reflects the light at thesecond side surface 20D. Further, another reflector 60 is arranged on asecond side surface 10D on the opposite side of the first side surface10C on the light-emitting device 31 side, and reflects the light at thesecond side surface 10D. This configuration increases an amount of lightemitted from the light-emitting device 31 to the first side surface 10Cof the first light-transmissive substrate 10 and the first side surface20C of the second light-transmissive substrate 20, and propagatingthrough a display panel 2. Further, the configuration improvesuniformity of the light propagating through the display panel 2.

The display apparatus 1 according to the third modification of the firstembodiment has no backlight device and no reflection plate on the firstprincipal surface 10A side of the first light-transmissive substrate 10or the first principal surface side of the second light-transmissivesubstrate 20, similarly to the first embodiment. This configurationallows a background on the first principal surface 20A side of thesecond light-transmissive substrate 20 to be visually recognized fromthe first principal surface 10A of the first light-transmissivesubstrate 10, or a background on the first principal surface 10A side ofthe first light-transmissive substrate 10 to be visually recognized fromthe first principal surface 20A of the second light-transmissivesubstrate 20.

Fourth Modification of First Embodiment

FIG. 22 is a plan view illustrating a plane of a display apparatusaccording to a fourth modification of the first embodiment. FIG. 23 is across-sectional view illustrating a cross-section taken along lineXXIII-XXIII′ in FIG. 22. The same configuration elements as thosedescribed in the above first embodiment are denoted with the samereference signs, and overlapping description is omitted. Thecross-section of XIII-XIII′ in FIG. 22 is the same as that of thedisplay apparatus of the first embodiment illustrated in FIG. 13, andthus overlapping description is omitted.

As illustrated in FIGS. 22 and 23, a light-emitting device 31 isprovided to face a fourth side surface 20F of a secondlight-transmissive substrate 20. As illustrated in FIG. 23, thelight-emitting device 31 irradiates the fourth side surface 20F of thesecond light-transmissive substrate 20 with light L. The fourth sidesurface 20F, which faces the light-emitting device 31, of the secondlight-transmissive substrate 20 serves as a light incident surface. Agap G is provided between the light-emitting device 31 and the lightincident surface. The gap G serves as an air layer.

As illustrated in FIG. 23, light L emitted from the light-emittingdevice 31 propagates in a direction away from the fourth side surface20F while being reflected at a first principal surface 10A of a firstlight-transmissive substrate 10 and a first principal surface 20A of thesecond light-transmissive substrate 20.

As illustrated in FIGS. 22 and 23, a reflector 60 that reflects thelight is provided on a third side surface 20E of the secondlight-transmissive substrate 20. The third side surface 20E isperpendicular to the first principal surface 20A of the secondlight-transmissive substrate 20. The light is reflected at the thirdside surface 20E by the reflector 60. The light reflected at the thirdside surface 20E propagates in a direction away from the third sidesurface 20E while being reflected at the first principal surface 10A ofthe first light-transmissive substrate 10 and the first principalsurface 20A of the second light-transmissive substrate 20.

A display apparatus 1 according to the fourth modification of firstembodiment includes the first light-transmissive substrate 10, thesecond light-transmissive substrate 20, a liquid crystal layer 50, thelight-emitting devices 31, and the reflectors 60. The two light-emittingdevices 31 are respectively arranged to face a first side surface 20Cand the fourth side surface 20F of the second light-transmissivesubstrate 20. The reflector 60 is arranged on a second side surface 20Don the opposite side of the first side surface 20C on the light-emittingdevice 31 side, and reflects the light at the second side surface 20D.Similarly, the reflector 60 is arranged on the third side surface 20E onthe opposite side of the fourth side surface 20F on the light-emittingdevice 31 side, and reflects the light at the third side surface 20E.According to this configuration, the light is reflected at the secondside surface 20D and the third side surface 20E by the two reflectors60, which decreases a difference between amounts of the light emittedfrom the two light-emitting devices 31 and propagating through thedisplay panel 2, and increases the amounts of the light emitted from thetwo light-emitting devices 31 and propagating through the display panel2. Further, the configuration improves uniformity of the lightpropagating through the display panel 2.

The display apparatus 1 according to the fourth modification of thefirst embodiment has no backlight device and no reflection plate on thefirst principal surface 10A side of the first light-transmissivesubstrate 10 or the first principal surface side of the secondlight-transmissive substrate 20, similarly to the first embodiment. Thisconfiguration allows a background on the first principal surface 20Aside of the second light-transmissive substrate 20 to be visuallyrecognized from the first principal surface 10A of the firstlight-transmissive substrate 10, or a background on the first principalsurface 10A side of the first light-transmissive substrate 10 to bevisually recognized from the first principal surface 20A of the secondlight-transmissive substrate 20.

In the display apparatus 1 according to the fourth modification of thefirst embodiment, one of the light-emitting devices 31 may be arrangedto face a first side surface 10C of the first light-transmissivesubstrate 10 and the first side surface 20C of the secondlight-transmissive substrate 20, and the other of the light-emittingdevices 31 may be arranged to face a fourth side surface 10F of thefirst light-transmissive substrate 10 and the fourth side surface 20F ofthe second light-transmissive substrate 20, similarly to the thirdmodification of the first embodiment. The reflector 60 may be arrangedon a second side surface 10D on the opposite side of the first sidesurface 10C on the light-emitting device 31 side, and reflect light atthe second side surface 10D. The cross-section taken along lineXIII-XIII′ in FIG. 22 may correspond to the cross-section illustrated inFIG. 21, and the reflector 60 may be arranged on the second side surface10D on the opposite side of the first side surface 10C on thelight-emitting device 31 side, and reflect the light at the second sidesurface 10D.

Second Embodiment

FIG. 24 is a plan view illustrating a plane of a display apparatusaccording to a second embodiment. FIG. 25 is a cross-sectional viewillustrating a cross-section taken along line XXV-XXV′ in FIG. 24. FIG.26 is a cross-sectional view illustrating a cross-section taken alongline XXVI-XXVI′ in FIG. 24. FIG. 27 is an explanatory view fordescribing a method of manufacturing a reflector of the displayapparatus according to the second embodiment. The same configurationelements as those described in the above first embodiment andmodifications thereof are denoted with the same reference signs, andoverlapping description is omitted.

A reflector 60A of the second embodiment is arranged at the position ofthe light-emitting device 31 according to the fourth modification of thefirst embodiment, and a light-emitting device 31 of the secondembodiment is arranged at the position of the reflector 60 according tothe fourth modification of the first embodiment.

As illustrated in FIGS. 24 and 25, the light-emitting device 31 isprovided to face a second side surface 20D of a secondlight-transmissive substrate 20. As illustrated in FIG. 25, thelight-emitting device 31 irradiates the second side surface 20D of thesecond light-transmissive substrate 20 with light L. The second sidesurface 20D, which faces the light-emitting device 31, of the secondlight-transmissive substrate 20 serves as a light incident surface. Agap G is provided between the light-emitting device 31 and the lightincident surface. The gap G serves as an air layer.

As illustrated in FIG. 25, the light L radiated from the light-emittingdevice 31 propagates in a direction away from the second side surface20D while being reflected at a first principal surface 10A of a firstlight-transmissive substrate 10 and a first principal surface 20A of thesecond light-transmissive substrate 20.

As illustrated in FIGS. 24 and 25, the reflector 60A that reflects thelight is provided on a first side surface 10C of the firstlight-transmissive substrate 10 and on a first side surface 20C of thesecond light-transmissive substrate 20. The first side surface 10C isperpendicular to the first principal surface 10A of the firstlight-transmissive substrate 10. The first side surface 20C isperpendicular to the first principal surface 20A of the secondlight-transmissive substrate 20. The light is reflected at the firstside surface 10C or the first side surface 20C by the reflector 60A. Thelight reflected at the first side surface 10C or the first side surface20C propagates in a direction away from the first side surface 10C orthe first side surface 20C while being reflected at the first principalsurface 10A of the first light-transmissive substrate 10 and the firstprincipal surface 20A of the second light-transmissive substrate 20.

As illustrated in FIGS. 24 and 26, a light-emitting device 31 isprovided to face a third side surface 20E of the secondlight-transmissive substrate 20. As illustrated in FIG. 26, thelight-emitting device 31 irradiates the third side surface 20E of thesecond light-transmissive substrate 20 with the light L. The third sidesurface 20E, which faces the light-emitting device 31, of the secondlight-transmissive substrate 20 serves as a light incident surface. Agap G is provided between the light-emitting device 31 and the lightincident surface. The gap G serves as an air layer.

As illustrated in FIG. 26, the light L radiated from the light-emittingdevice 31 propagates in a direction away from the third side surface 20Ewhile being reflected at the first principal surface 10A of the firstlight-transmissive substrate 10 and the first principal surface 20A ofthe second light-transmissive substrate 20.

As illustrated in FIGS. 24 and 26, a reflector 60A that reflects thelight is provided on a fourth side surface 10F of the firstlight-transmissive substrate 10 and on a fourth side surface 20F of thesecond light-transmissive substrate 20. The fourth side surface 20F isperpendicular to the first principal surface 20A of the secondlight-transmissive substrate 20. The fourth side surface 10F isperpendicular to the first principal surface 10A of the firstlight-transmissive substrate 10. The light is reflected at the fourthside surface 10F or the fourth side surface 20F by the reflector 60. Thelight reflected at the fourth side surface 10F or the fourth sidesurface 20F propagates in a direction away from the fourth side surface10F or the fourth side surface 20F while being reflected at the firstprincipal surface 10A of the first light-transmissive substrate 10 andthe first principal surface 20A of the second light-transmissivesubstrate 20.

The reflector 60A of the second embodiment is a reflection film formedby sputtering of a metal such as aluminum or silver. Any material can beused for the reflector 60A as long as the material has high reflectance.As illustrated in FIG. 27, the first light-transmissive substrates 10and the second light-transmissive substrates 20 are arranged in a stateof being bonded together, and the reflectors 60A are collectively formedon a plurality of display panels. The reflector 60A of the displayapparatus according to the second embodiment can have the same structureas any of the reflectors 60 and 65 described in the first embodiment andmodifications thereof.

The display apparatus 1 according to the second embodiment includes thefirst light-transmissive substrate 10, the second light-transmissivesubstrate 20, a liquid crystal layer 50, the light-emitting devices 31,and the reflectors 60A. The two light-emitting devices 31 arerespectively arranged to face the second side surface 20D and the thirdside surface 20E of the second light-transmissive substrate 20. One ofthe reflectors 60A is arranged on the first side surface 20C and thefirst side surface 10C on the opposite side of the second side surface20D on the light-emitting device 31 side, and reflects light at firstside surface 20C or the first side surface 10C. Similarly, the other ofthe reflectors 60A is arranged on the fourth side surface 20F and thefourth side surface 10F on the opposite side of the third side surface20E on the light-emitting device 31 side, and reflects light at thefourth side surface 20F or the fourth side surface 10F. According tothis configuration, the two reflectors 60 reflect light at the firstside surface 20C, the first side surface 20C, the fourth side surface20F, or the fourth side surface 10F, which reduces a difference betweenamounts of the light emitted from the two light-emitting devices 31 andpropagating through the display panel 2, and increases the amounts ofthe light emitted from the two light-emitting devices 31 and propagatingthrough the display panel 2. Further, the configuration improvesuniformity of the light propagating through the display panel 2. Therespective reflectors 60A may be individually provided on the first sidesurface 20C and the first side surface 20C, and the respectivereflectors 60A may be individually provided on the fourth side surface20F and the fourth side surface 10F.

In the second embodiment, one of the reflectors 60A may be arranged on asecond side surface 10D on the opposite side of the first side surface10C on the light-emitting device 31 side, and the other of thereflectors 60A may reflect the light at the second side surface 10D.

The display apparatus 1 according to the second embodiment has nobacklight device and no reflection plate on the first principal surface10A side of the first light-transmissive substrate 10 or the firstprincipal surface 20A side of the second light-transmissive substrate20, similarly to the first embodiment. This configuration allows abackground on the first principal surface 20A side of the secondlight-transmissive substrate 20 to be visually recognized from the firstprincipal surface 10A of the first light-transmissive substrate 10, or abackground on the first principal surface 10A side of the firstlight-transmissive substrate 10 to be visually recognized from the firstprincipal surface 20A of the second light-transmissive substrate 20.

By applying the second embodiment to the first embodiment, the reflector60A of the second embodiment may be arranged at the position of thelight-emitting device 31 according to the first embodiment, and thelight-emitting device 31 of the second embodiment may be arranged at theposition of the reflector 60 according to the first embodiment.

Preferred embodiments of the present disclosure have been described.However, the present disclosure is not limited by these embodiments. Thecontent disclosed in the embodiments is merely an example, and variousmodifications can be made without departing from the gist of the presentdisclosure. Appropriate modifications made without departing from thegist of the present disclosure obviously belong to the technical scopeof the present disclosure. All the technologies that can beappropriately designed, modified, and implemented by a person skilled inthe art on the basis of the above-described disclosure belong to thetechnical scope of the present disclosure as long as the technologiesinclude the gist of the present disclosure.

For example, the display panel 2 may be a passive matrix panel without aswitching element. The passive matrix panel includes, in plan view, afirst electrode extending in an X direction, a second electrodeextending in a Y direction, and wiring electrically coupled with thefirst electrode or the second electrode. The first electrode, the secondelectrode, and the wiring are formed of, for example, ITO. For example,the first light-transmissive substrate 10 including the above-describedfirst electrode, and the second light-transmissive substrate 20including the second electrode are arranged to face each other with theliquid crystal layer 50 interposed therebetween.

The example in which the first orientation film 55 and the secondorientation film 56 are the vertical orientation films has beendescribed. However, the first orientation film 55 and the secondorientation film 56 may be horizontal orientation films. The firstorientation film 55 and the second orientation film 56 only need to havea function to orient the monomers in a predetermined direction inpolymerizing the monomers. This allows the monomers to become polymersoriented in the predetermined direction. When the first orientation film55 and the second orientation film 56 are the horizontal orientationfilms, the direction of the optical axis Ax1 of the bulk 51 and thedirection of the optical axis Ax2 of the fine particle 52 are the same,and are perpendicular to the Z direction, in a state in which no voltageis applied between the pixel electrode 16 and the common electrode 22.The direction perpendicular to the Z direction corresponds to the Xdirection or the Y direction along a side of the firstlight-transmissive substrate 10 in plan view.

What is claimed is:
 1. A display apparatus comprising: a firstlight-transmissive substrate; a second light-transmissive substratearranged to face the first light-transmissive substrate; a liquidcrystal layer including polymer dispersed liquid crystals sealed betweenthe first light-transmissive substrate and the second light-transmissivesubstrate; at least one light-emitting device arranged to face at leastone of a side surface of the first light-transmissive substrate or aside surface of the second light-transmissive substrate; and at leastone reflector arranged on at least one of a side surface of the firstlight-transmissive substrate or a side surface of the secondlight-transmissive substrate, the side surface of the first or secondlight-transmissive substrate being on an opposite side of the sidesurface of the first or second light-transmissive substrate to which theat least one light-emitting device faces, and configured to reflectlight at the side surface on the opposite side.
 2. The display apparatusaccording to claim 1, wherein the first light-transmissive substrateincludes a first principal surface and a second principal surface thatis a plane parallel to the first principal surface, the secondlight-transmissive substrate includes a first principal surface and asecond principal surface that is a plane parallel to the first principalsurface, and when the polymer dispersed liquid crystals are in anon-scattering state, a background on the first principal surface sideof the second light-transmissive substrate is visually recognized fromthe first principal surface of the first light-transmissive substrate,or a background on the first principal surface side of the firstlight-transmissive substrate is visually recognized from the firstprincipal surface of the second light-transmissive substrate.
 3. Thedisplay apparatus according to claim 1, wherein the firstlight-transmissive substrate includes a first principal surface and asecond principal surface that is a plane parallel to the first principalsurface, the second light-transmissive substrate includes a firstprincipal surface and a second principal surface that is a planeparallel to the first principal surface, and a side surface of the firstlight-transmissive substrate is perpendicular to the first principalsurface of the first light-transmissive substrate, and a side surface ofthe second light-transmissive substrate is perpendicular to the firstprincipal surface of the second light-transmissive substrate.
 4. Thedisplay apparatus according to claim 1, wherein the at least onereflector is a reflection film.
 5. The display apparatus according toclaim 1, wherein the at least one reflector is a paste-like reflectionfilm.
 6. The display apparatus according to claim 1, wherein the atleast one reflector is a reflection film formed by sputtering.
 7. Thedisplay apparatus according to claim 1, wherein the at least onereflector is a retroreflection structural body in which light havingentered therein at an incident angle is reflected at an emission anglethat is the same angle as the incident angle.
 8. The display apparatusaccording to claim 1, wherein an area of the first light-transmissivesubstrate is larger than an area of the second light-transmissivesubstrate in plan view, the at least one light-emitting device isarranged to face a side surface of the first light-transmissivesubstrate and a side surface of the second light-transmissive substrate,and the at least one reflector comprises two reflectors, and the tworeflectors are arranged on respective two side surfaces of the secondlight-transmissive substrate, each of the two side surfaces being on anopposite side of the side surface of the second light-transmissivesubstrate to which the at least one light-emitting device faces.
 9. Thedisplay apparatus according to claim 1, wherein an area of the firstlight-transmissive substrate is larger than an area of the secondlight-transmissive substrate in plan view, the at least onelight-emitting device comprises two light-emitting devices, and the twolight-emitting devices are arranged to face respective two side surfacesof the second light-transmissive substrate, and the at least onereflector comprises two reflectors, and the two reflectors are arrangedto face respective two side surfaces of the first light-transmissivesubstrate and respective two side surfaces of the secondlight-transmissive substrate.